[Effect of digitalis on contractility of the failing right and left ventricles during exercise (authors transl)].

Intra-venticular pressures were measured at rest and during simulated exercise before and after intravenous administration of 0.6 mg beta-methyldigoxin in 16 patients (right ventricular measurements in 11, left ones in five), measurements in the right ventricle being taken before and 30-45 min after, in the left ventricle before and 20 min after injection of the drug. There was an increase in stroke volume and maximal cardiac work, while end-diastolic pressure fell. Cardiac glycosides can, therefore, favourably influence congestive cardiac failure on physical exertion. Digitalization indicated in those patients who, on exercise, have an increased end-diastolic pressure and reduced contractility. The positive digitalis effect consists of improved contractility and sustained reduction in end-diastolic pressure. On maintenance digitalization it is to be expected that the heart will profit from both mechanisms, both at rest and during exercise. The increased contractility caused by the glycosides is, however, so small that it does not cause any significant change in oxygen consumption.